There have been reported numerous compounds having herbicidal activity for weed control.
For example, U.S. Pat. No. 4,130,413 discloses a compound of formula (II):

wherein, A is O, S or NH; R1 is hydrogen, halogen, CF3, NO2, CN or alkyl; R2 is hydrogen or alkyl; Z is —CON—R9R10, R9 and R10 being each independently C1-6 alkyl, C1-6 hydroxyalkyl, C3-6 cycloalkyl, C1-4 alkoxy or phenyl, substituted with 1 to 3 substituents selected from the group consisting of hydrogen, C1-4 alkyl, C1-6 alkoxy, halogen and CF3; and m is 0, 1 or 2.
U.S. Pat. No. 4,531,969 discloses a compound of formula (III):

wherein, R5 is
R6 being hydrogen or halogen, R7 being hydrogen or alkyl; Z is —CON—R9R10, R9 and R10 being each independently C1-6 alkyl, C1-6 hydroxyalkyl, C3-6 cycloalkyl, C1-4 alkoxy or phenyl, substituted with 1 to 3 substituents selected from the group consisting of hydrogen, C1-4 alkyl, C1-6 alkoxy, halogen and CF3.
U.S. Pat. No. 5,254,527 discloses a compound of formula (IV):

wherein, R5 and Z have the same meanings as defined above.
Japanese Laid-open Patent Publication No. Hei 2-11580 discloses a compound of formula (V).

wherein, L is low alkyl, halogen, methoxy, methoxyphenoxy, benzyloxy, methylthio or methylvinyl; n is 0 or 2.
The above-mentioned compounds are satisfactory in terms of selectivity and safety for desired crop plants, but not completely satisfactory for the weed control.